To prevent contamination in a cylinder by the gas exchange action in the cylinder at a cylinder halt operation, improve an exhaust emission performance, prevent the occurrence of deposits or the like, and effectively suppress the occurrence of torque shock at a cylinder halt shifting.

A variable valve device, in which a part of cylinders stopped according to a engine operation condition, is provided with a first variable mechanism 1 for variably controlling the lifting amounts of an intake valve 12 and an exhaust valve by rotation controlling a control cam 33 via a control shaft 32 for charging the turning fulcrum of a locker arm 23. When, for example, changing the maximum valve lifting phases of the intake and exhaust valves, respectively from the maximum lifting to an intermediate one, according to the engine operation condition, the phase is controlled so as to move to the vicinity of a bottom dead center through an intermediate phase position between a present valve lifting phase position and the bottom dead center of a piston.